Effects of a synthetic retinoid on skin structure, matrix metalloproteinases, and procollagen in healthy and high-risk subjects with diabetes

BACKGROUND: In diabetes, foot ulceration may result from increased skin fragility. Retinoids can reverse some diabetes-induced deficits of skin structure and function, but their clinical utility is limited by skin irritation. The effects of diabetes and MDI 301, a nonirritating synthetic retinoid, and retinoic acid have been evaluated on matrix metalloproteinases (MMPs), procollagen expression, and skin structure in skin biopsies from nondiabetic volunteers and diabetic subjects at risk of foot ulceration using organ culture techniques. METHODS: Zymography and enzyme-linked immunosorbent assay were utilized for analysis of MMP-1, -2, and -9 and tissue inhibitor of metalloproteinase-1 (TIMP-1) and immunohistochemistry for type I procollagen protein abundance. Collagen structure parameters were assessed in formalin-fixed, paraffin-embedded tissue sections. RESULTS: The % of active MMP-1 and -9 was higher and TIMP-1 abundance was lower in subjects with diabetes. Type 1 procollagen abundance was reduced and skin structural deficits were increased in diabetes. Three μM MDI 301 reduced active MMP-1 and -9 abundance by 29% (P